package org.bouncycastle.asn1.x500;

import org.bouncycastle.asn1.ASN1Encodable;
import org.bouncycastle.asn1.ASN1Object;
import org.bouncycastle.asn1.ASN1ObjectIdentifier;
import org.bouncycastle.asn1.ASN1Primitive;
import org.bouncycastle.asn1.ASN1Sequence;
import org.bouncycastle.asn1.DERSequence;

/**
 * Holding class for the AttributeTypeAndValue structures that make up an RDN.
 */
public class AttributeTypeAndValue
    extends ASN1Object
{
    private ASN1ObjectIdentifier type;
    private ASN1Encodable       value;

    private AttributeTypeAndValue(ASN1Sequence seq)
    {
        type = (ASN1ObjectIdentifier)seq.getObjectAt(0);
        value = (ASN1Encodable)seq.getObjectAt(1);
    }

    public static AttributeTypeAndValue getInstance(Object o)
    {
        if (o instanceof AttributeTypeAndValue)
        {
            return (AttributeTypeAndValue)o;
        }
        else if (o != null)
        {
            return new AttributeTypeAndValue(ASN1Sequence.getInstance(o));
        }

        throw new IllegalArgumentException("null value in getInstance()");
    }

    public AttributeTypeAndValue(
        ASN1ObjectIdentifier type,
        ASN1Encodable value)
    {
        this.type = type;
        this.value = value;
    }

    public ASN1ObjectIdentifier getType()
    {
        return type;
    }

    public ASN1Encodable getValue()
    {
        return value;
    }

    /**
     *  
     * AttributeTypeAndValue ::= SEQUENCE {
     *           type         OBJECT IDENTIFIER,
     *           value        ANY DEFINED BY type }
     * </pre>
     * @return a basic ASN.1 object representation.
     */
    public ASN1Primitive toASN1Primitive()
    {
        return new DERSequence(type, value);
    }
}
